The cell and molecular pathology Core provides a variety of cell assays for all projects within the Program Project. Both high resolution standard cytogenetic evaluations and fluorescence in situ hybridization will be performed on cultures of human, mouse and chicken cells for program projects. Both standard cell cycle-apoptosis and specialized flow cytometric analyses will be performed for all projects, including assays for proliferative survival and recombination assays. The Core will provide comprehensive histopathology service in the interpretation of murine and human tumors and maintenance of a sarcoma cell bank. A collaborative effort with the first project will include provision of purified DNA and RNA from sarcomas for the identification of p01ymorphisms and mutations in the WRN gene. The Core will provide Program Project-wide quality assurance service for verification of cell identities by karyotyping, WRN microsatellite identity testing, and genotyping. This core will provide these comprehensive services to facilitate accurate and efficient cross-fertilization among the projects.